With a construction machine such as a hydraulic power shovel or the like, it is desirable to plan for enhancement of energy saving when driving the machine, or when performing various different types of work. Thus, in the prior art, such machines have been proposed, which can be changed over to energy saving driving when the actual fuel consumption (the actual fuel consumption ratio) does not reach a reference value (a fuel consumption ratio which is taken as a reference) (for example, refer to Patent Reference #1). Furthermore, there are such machines which are capable of calculating the work amount and the fuel consumption, and of analyzing whether the working efficiency is good or bad (for example, refer to Patent Reference #2).
In other words, with the construction machine 1 described in the above Patent Reference #1, the fuel which is actually consumed is calculated, and from this an actual fuel consumption is calculated as the fuel consumption amount per unit time. This actual fuel consumption is compared with a reference value which is set in advance, and, when the actual fuel consumption is less than its reference value, then changeover to energy saving driving is performed. Furthermore, with the construction machine described in Patent Reference #2, the work amount is detected by a detection device which consists of an engine rotational speed sensor, a fuel sensor, and a sensor for load detection or the like, and the work amount and the fuel consumption for a cycle time are calculated, whence the work amount per time and the work amount per fuel consumption are calculated; and this work amount per time and work amount per fuel consumption which have been calculated are printed out.
Patent Reference #1: Japanese Patent Laid-Open Publication 2002-285890 (claims 3 to 4, FIG. 1)
Patent Reference #2: Japanese Patent 2,534,880 (claims 3 to 4, FIG. 1)
In this manner, in the prior art, it has been possible to perform energy saving driving with a construction machine. However, with the construction machine as described in the above Patent Reference #1, although energy saving driving can be shifted to after the fuel consumption has become bad, it is not possible to shift to energy saving driving if the fuel consumption does not actually become bad. In other words, it becomes possible automatically to shift to energy saving driving when the fuel consumption during actual use has become bad. Furthermore, with the construction machine as described in the above Patent Reference #2, the work amount per time and the work amount per fuel consumption are only written (displayed) upon a report. Due to this, even if the operator looks at this report, he will not necessarily perform driving leading to improvement of the fuel consumption, and this does not make contribution to attainment of energy saving.